Chapter 2 SUmmative Flashcards
What is a significant figure?
Measurement needed to convey precision; Digits in a number that carry meaning contributing to its measurement
How many significant figures are in the number 0.0001. Why?
One; Because all leading zeroes are not considered significant
How many significant figures are in the number 0.005200?
Four; Because leading zeroes ar e not considered significant, while any numbers after .0052 are significant because they measure precision.
How many significant figures are in 370.
All 3; Because since the decimal point is there, it shows that the measurement was measured to be exactly 370.
How many sig figs are in 10.0?
3; Because the zero further shows precision of the measurement.
How many sig figs are in the number 701.802
6; because when you have non zero digits on both ends, all numbers in between are significant
How many sig figs are in 37000?
2; Because the zeroes after are not precise because there are no decimal points to show precision.
How would you show more precision with sig fig?
You would put a decimal point in to show where you measured to.
What happens if you add or subtract sig figs?
If you add or subtract, the answer is
rounded to the same number of decimal
places as the measurement with the least
number of decimal places.
What happens if you multiply or divide sig figs?
the answer is rounded off to the number
of significant figures in the least precise
term used in the calculation (i.e. the
number with the fewest sig figs).
What is scientific notation?
Scientific notation is the way that scientists easily handle very large numbers or very small numbers. For example, instead of writing 0.0000000056, we write 5.6 x 10-9.
What are the steps of scientific notation?
1) move the decimal point to obtain a coefficient that is at least 1 but less than 10.
2) move decimal place to the right or left and express this as a power (right= negative, left=positive)
3) Write the product of coefficient multiplied by 10
How do you do dimensional analysis?
You do the amount of the unit multiplied by (usually) the single unit on the denominator and how many of that go into the top on the numerator.
x * y/x or x * a/x * x/b etc.
How do the metric symbols (Tera, giga, hexa, deci, etc) work with dimensional analysis?
Use the acronym (The greatest man King Henry doesn’t usually drink chocolate milk minding nasty people)
-From the world Usually, which is 10^0, work outwards.
For example, for deci, it would be 10 of the units that fit into the centra; unit. For milli, it would be 1000.
-Just simply work outwards from base unit
what is the difference between precision and accuracy
Accuracy is how close a measurement comes to the truth, such as how close darts are to the bullseye; Precision is how close a measurement comes to another measurement, like how close two darts come to one another
